Sl 4.x / slc 4.x

In October 2011, X.Org issued a faulty update to the xorg-x11 packages (“6.8.2-1.EL.70”) that causes OpenGL (GLX) applications to fail on SL4X and SLC4X (but it does not seem to affect SL5X / SLC5X).
Applications (e.g. the standard “glxinfo” and “glxgears”) die with an error:

X Error of failed request: BadLength (poly request too large or internal Xlib length error)
Major opcode of failed request: 143 (GLX)
Minor opcode of failed request: 20 (X_GLXClientInfo)
Serial number of failed request: 13
Current serial number in output stream: 17

The fix is to downgrade the xorg-x11 packages to the previous version (from “EL.70” to “EL.69”).
For example, on a SLC 4.X / i386 (32-bit) machine, login as “root”, then: cd /tmp rm -f xorg-x11-*.EL.69.i386.rpm for i in `rpm -qa|grep '^xorg-x11.*6.8.2-1.EL.70$'|sed '{s/.EL.70$/.EL.69.i386.rpm/}'`; do wget${i}; done rpm --oldpackage -Uvh xorg-x11-*.EL.69.i386.rpm rm -f xorg-x11-*.EL.69.i386.rpm rpm -qa|grep '^xorg-x11.*6.8.2-1.EL.69$' >> /etc/yum/pluginconf.d/versionlock.list sync shutdown -r now

P.S. If you want to compile the newest ROOT 5.34 on a SL© 4.X machine, see: [url]Problems with in ROOT 5.34.01

Thank you very much.